1. Field of the Invention
The present invention relates to a housing holding electronic components and a motor drive system including that housing.
2. Description of the Related Art
A motor drive system for driving a machine tool is used in an environment in which dust, cutting fluid, and other foreign matter fills the air. The electronic components forming the motor drive system are housed in a control panel having the form of a locker and are protected from that foreign matter. However, in actuality, it is difficult to completely prevent foreign matter from entering the inside of the control panel.
If foreign matter sticks to the electronic components inside of the control panel, over the years, it will cause the electronic components to corrode and can cause the motor drive system to malfunction. Therefore, proposals have been made to prevent deposition of foreign matter or identify deposition of foreign matter early.
Japanese Patent Publication No. 2006-019405A discloses a printed circuit board including a circuit for detecting deterioration or malfunction of the printed circuit board occurring due to foreign matter, for example, dust or cutting fluid, deposited on the printed circuit board.
According to the related art, to prevent foreign matter from depositing on electronic components, a mechanism has been provided for guiding cutting fluid away from the housing of the electronic components or the electronic components have been arranged at locations resistant to deposition of cutting fluid. Alternatively, to prevent cutting fluid from filling the air, it has been proposed not to use a fan motor for cooling use.